Denture-characterizing process



June 12, 1956 L GRANDE OGLESBY EFAL 2,750,318

DENTURECHARACTERIZING PROCESS Filed March 27, 1952 3 Sheets-Sheet 1 v dINVENTORS LaGran e Oglesby 2 BY Hobart H. Proctor Fig. 9

June 12, 1956 LA GRANDE OGLESBY ETAL 2,750,318

DENTURE-CHARACTERIZING PROCESS 3 Sheets-Showv 2 Filed March 27, 1952 Fig.

Fig.

E .m F

INVENTORS La Grande Oglesby BY Hobart H. Proctor June 12, 1956 LA GRANDE OGLESBY ETAL 2,750,318

DENTURE-CHARACTERIZING PROCESS Filed March 27. 1952 3 Sheets-Sheet 3 4a 42 44 l 292 7 2 7 W w I I /II M I), 1' 25/ x Fig. '9 44? NW: MMJIWXQ X INVEN TOR La Grande Oglesiy BY Hobart H.= Proctor DENTURE-CHARACTERIZING PROCESS La Grande Ogleshy, Edgewater, and Hobart H. Proctor, Denver, Colo.

Application March 27, 1952, Serial No. 278,796

Claims. (Cl. 154-410) This invention relates to the art and practice of prosthetic dentistry as particularly exemplified in the production of dentures and has as an object to provide a novel and improved process for the constitution of dentures distinguished by a natural, life-like appearance.

A further object of the invention is to provide a novel and improved process of denture production adaptable to develop in prosthetic appliances a close simulation of the natural appearance and relationships distinguishing the gingival and alveolar mucosa of any particular individual.

A further object of the invention is to provide a novel and improved process of denture production efiective to characterize and individualize prosthetic appliances according to the natural gingival and alveolar manifestations of the wearer.

A further object of the invention is to provide a novel and improved process of denture production characterized by a technique adaptable in detail to vary and particularize individual prosthetic appliances in close simulation of the natural gingival and alveolar manifestations of the ultimate wearer.

A further object of the invention is to provide a novel and improved process for the characterizing and individualizing of denture base exposures that is susceptible of convenient and successful practice through the use of known and readily-available facilities and materials, that maintains established standards of denture product quality, and that advantageously and pleasingly distinguishes the resultant dentures.

With the foregoing and other objects in view, our invention consists in the nature and sequential relation of cps, and in the process thereby comprised, as hereinafter described, pointed out in our claims, and typified by the accompanying drawings, in which- Figure 1 is a plan view of a typical denture-forming flask section as conventionally conditioned for an initial phase of denture production. Figure 2 is a plan view of a flask section complementary to that shown in Figure 1 as conditioned for coaction with its complement. Figure 3 is a cross section through an assembly of the flask sections shown in Figures 1 and 2 as related to effectuate a first step of the improved process. Figure 4 is a side elevation of a denture base form or pattern resulting from the operation represented by Figure 3. Figure 5 is a cross section taken substantially on the indicated line 55 of Figure 4 and illustrating a conditioning of the pattern of Figure 4 appropriate to practice of the improved process. Figure 6 is an elevation, partially in section, of the pattern of Figure 4 as invested relative to a flash section similar to but other than that shown in Figure 1. Figure 7 is an elevation of the assembly according to Figure 6 as worked and modified in accordance with the principles of the invention. Figure 8 is a cross section taken substantially on the indicated line 8--8 of igure 7. Figure 9 is a cross section through a full flash investiture completed relative to the section assembly of Figures 7 and 8. Figure 10 is a plan view of the lower flask section of Figure 9 with the pattern of Figure 4 nited States Fatent 6 2,750,312? Patented June 12, 1956 ice removed and as conditioned for subsequent steps of the improved process. Figure 11 is a plan view of the upper flask section of Figure 9 as inverted, freed from the pattern of Figure 4, and conditioned for subsequent operations. Figure 12 is a diagrammatic representation of material suitable for use in the construction of denture bases as prepared and formed for use in the practice of the improved process. Figure 13 is a plan view of one of the material units shown in Figure 12 as further conditioned in accord with the principles of the invention. Figure 14 is a fragmentary, detail view diagrammatically representing a source and evolvement of fibrous material utilized in practice of the improved process. Figure 15 is a fragmentary, detail, isometric View, on a much enlarged scale, of the modified base-forming material typified by Figure 13. Figure 16 is a view of the flask section organization shown in Figure 11 as further worked and conditioned in accordance with the principles of the invention. Figure 17 is a cross section similar to Figure 9 representing the flask sections of Figures '10 and 11 as assembled to coact in a final stage of their use. Figure 18 is a side elevation of a denture base portion resulting from the coaction of flask sections represented by the preceding view. Figure 19 is a plan view of the base portion of Figure 18 as invested in the flask section of Figure l and conditioned for subsequent steps of the process. Figure 20 is a cross section through the organization of Figure 19 and the flask section of Figure 2 as assembled in and to perfect a denture-completing phase of the process. Figure 21 is a side elevation of a completed denture resulting from application of the process represented by the sequence of illustrated steps.

Production of satisfactory prosthetic dental appliances has been much facilitated and advanced through the development of acrylic polymers, plastic teeth, and expedient laboratory techniques, the materials and practices now available permitting pigmentation of the denture base in natural color tones and very precise matching of the artificial teeth to the appearance of those they replace. However, inadequacies of conventional practices are apparent in their failure to present any effective ap proximation of the natural color contrast obtaining between the gingival and alveolar zones of the original dentition and in their failure to simulate the veining of the gingival zone labial aspect in any practical or persuasively-natural manner. That the naturalness of appearance characterizing a denture is of consequence to the wearer requires no elaboration, and that a process of denture production which enhances the natural appearance of the appliance in use is advantageous is similarly manifest, hence the instant invention is directed to the provision of such a process. Briefly, then, the invention resides in a process or method for the production of a denture of conventional general construction characterized by a veined gingival zone and an unveined alveolar zone distinguished as to color tone in an association closely simulating the appearance of the corresponding natural elements of the wearer for whom the appliance is designed.

Practice of the improved process begins with a conventional preliminary or preparatory stage wherein data obtained by the dental operator is embodied in and as a wax replica of the desired denture base carrying the se lected teeth in the arrangement and interasso'ciation ultimately desired and such toothed replica is utilized for the production of a mold or matrix within the separable, complementary sections 25 and 26 of the flask. As represented by Figures 1, 2 and 3, the flask section 25 carries the matrix face corresponding to the side of the denture replica, known as the model side, remote from the teeth as a development in and on the plaster charge 27 of the section reflecting a disposition of the said replica with its periphery, or arcuat'e edge margin remote from the teeth, substantially coplanar with the area of flask section separation, while the flask section 26 carries the matrix face corresponding to the toothed side of the denture replica developed in and on the plaster charge 28 of said section with the teeth 29 of the ultimate denture firmly embedded in the customary stone cap portion of the section charge so that removal of the wax portion of the denture replica after completion of the matrix as aforesaid leaves the teeth 29 with their bases obtruding within the matrix cavity definitive of the denture alveolar ridge. After complete setting of the plaster charges and 27 of the investment shown and above described, the flask sections 25 and 26 are separated, the wax portion of the denture replica removed, and the mold cavities, or matrix faces, cleaned to condition them ready for subsequent use.

Giving effect to the novel principles of the invention in a departure from conventional practices, the matrix characterizing the flask sections 25 and 26 is utilized for the production of a wax pattern 30, Figure 4, of the labial portion of the ultimately-desired denture base, which pattern 3!) is formed by first covering both tooth and model sides of the matrix labial zone with thin, flexible, impervious sheets 31 of suitable parting material, such as cellophane, pressing and packing base plate wax at appropriate working temperature in and to fill the matrix labial zone, assembling the flask sections 25 and 26 as shown in Figure 3 to shape the wax charge into conformity with the matrix, then separating the flask sections, removing the shaped pattern, and finally stripping away the parting material to free and expose the desired pattern. After its removal from the matrix, the pattern is firmed and stiffened by means of a plaster rib 32 poured within and filling the arcuate channel opening through the model side of the pattern away from the alveolar ridge thereof.

The pattern 3%, formed and firmed as above described, is next invested in and on the plaster charge 33 of a flask section 25, conveniently identical with but other than the section 25, with its periphery substantially coplanar with the area of flask section separation, as shown in Figure 6, whereafter the marginal serrations and identations indicative of tooth form and position are trimmed away to depress, modify, and regularize the exposed ridge border of the pattern and, an important feature of the invention, the angle between the labial face and alveolar ridge portions of the pattern is cut away to leave a succession of shallow cups or scallops 34 each registered with and inclining outwardly from a tooth position as indicated on the pattern, thus to eliminate from the pattern 30 that portion corresponding to the non-vascular natural gum tissue adjoining and surrounding the bases of the teeth and to establish a sinuous line of scallop 34 intersection with the labial face. of the pattern which closely simulates in form and position the line of vascular and non-vascular tissue junction manifest on the labial exposure of a natural gum. Mounted, trimmed, and scalloped as above set forth, the pattern 30 is substantially as represented by Figures 7 and 8.

Trimming and shaping of the invested pattern 30 hav ing been completed, flasking of the pattern is perfected by means of a flask section 26' complementary to the section 25 and containing a plaster charge 35 coactable with the charge 33 of the section 25' to define a mold or matrix shaped by and conformed to the pattern 30.

The matrix developed from the pattern 30 in the flask sections 25' and 26 is utilized for the production of a permanent denture base portion corresponding to said pattern and selectively characterized to simulate the vascular gingival zone of the individual for whom the denture is designed. A suitable, commercial, acrylic, denture base material is conventionally prepared as a dough conditioned for packing within a matrix and is tinted by established means and techniques to a color tone matching the natural gum color of the ultimate denture wearer, the so-prepared acrylic dough is pressed, as between flat, rigid sheets or plates, into wafers of appropriate size and thickness which are then cut into arcuate segments 36, Figures 12 and 13, generally conformable with the analogous areas of the matrix characterizing the flask sections 25' and 26'. Fine, vein-simulating fibers 37 of a color to match the vein system of the ultimate wearers gum exposure are obtained, conveniently through unraveling of a selected, fast-color, rayon yarn or thread 38 as indicated by Figure 14, and said fibers 37 are laid in a pattern typical of natural veining on and to substantially cover a surface of an adequate number of the segments 36 and are tacked or held to and in the desired patterned relation with the segment surfaces by means of a convenient spot binder, such as an acrylic monomer, at least one of the said seg ments 36 preferably being kept free of the fibers 37, for reasons that will hereinafter appear. The segments 36 having been prepared as above discussed, the matrix faces presented by the flask sections 25 and 26 are covered with metal foil, as at 39 in Figures 10 and 11, conformed to the surface variations of the matrix for the purpose of hygroscopically insulating the matrix-defining material of the flask section charges from the acrylic material introduced within the matrix, and a sheet of parting material such as cellophane, indicated at 40 in Figures 16 and 17, is laid over each face of the matrix exposed by the separated flask sections 25' and 26 and the said matrix is then progressively packed with the fiber-patterned se ments 36 until almost full, the said segments being fitted and applied to the matrix as successive laminations whereof the sides carrying the fibers 37 are directed away from the labial face or aspect of the matrix, thus to embed the fibers 37 carried by the successive segments 36 within the matrix charge and at various distances inwardly of such charge from the matrix labial face. Corn pleting the packing of the matrix, a segment 36 free from fibers 37 is last applied to the matrix charge to cover and embed all of the fibers 37 otherwise exposed, and, in a final assembly of the flask sections 25' and 26' represented by Figure 17 the matrix charge is compressed and shaped into conformity with the matrix and hence into a denture base portion 41 of uncured acrylic material corresponding to the trimmed pattern 30 from which the matrix was developed.

The so-molded acrylic denture base portion 41, characterized by a vascular appearance deriving from the fibers 37 embedded therein, is removed from the matrix of the flask sections 25 and 26, stripped free from any adhering parting material, and placed in position on and in registration with the model side or matrix face of the flask section 25 with which it conforms, a sheet 42 of parting material being expediently interposed between the engaging areas of said base portion and flask section matrix and charge. With the base portion 41 in place on the flask section 25, the palatal or lingual area of the associated matrix is packed with suitably-tinted, acrylic dough as indicated at 43 in Figure 19 and separate, small pads 44 of such dough are arranged in and over the marginal concavities of the portion 41 corresponding to the scallops 34 of the pattern 30, one such pad 44 being applied to each of the said concavities registrable with a tooth 29 position, whereafter the flask section 26 carrying the teeth 29 is mated with the flask section 25, as in Figure 20, the tooth bases exposed in the matrix portion of said section 26 having first been coated with a suitable bonding agent, and the resulting flask section assembly is then pressed to a final closure in a usual manner to spread and form the acrylic dough material 43 as an integral, matrix-filling extension of the base portion 41, to seat the tooth bases in the acrylic dough pads 44, and to distribute the pad 44 material about and between the tooth bases in filling relation with the adjacent matrix zone represented by the material trimmed and cut away from the pattern 30 in the development of the scallops 34 of the latter, thus to associate the unfibered acrylic dough of the pads 44 with the fibered body of the pattern 41 as a sinuously-outlined, integrally-related band 45 engaged about and between the tooth bases in close simulation of the non-vascular, alveolar zone characterizing a natural denition. The compressed flask section assembly constituted as just described is subjected to a heat treatment appropriate to permanently set and cure the acrylic materials employed to form the denture, as is conventional technique, Whereafter separation of the flask sections 25 and 26 releases the completed denture unit 46 of Figure 21 ready for polishing, final fitting, and use.

It is to be noted that the denture unit 46 resulting from practice of the improved process is a homogeneous, simultaneously-cured combination of the denture base portion 41 carrying the embedded fibers 37 in simulation of the color tone and vascular arrangement of the natural dentition it is designed to represent and the unfibered band 45 tinted and disposed in close simulation of the corresponding zone of the natural dentition to mount and secure the teeth 29. The fibers 37 exposed through the surfaces of the denture base portion 41 are embedded in the base portion material at varying depths inwardly thereof from the surface of their exposure in a natural, visually-persuasive manner, and since none of said fibers lie at or intersect the surface of their exposure, polishing, fitting, and other operations applied to alter and modify the denture unit surfaces do not affect the color tone or vascular visual effect of the unit.

Since changes, variations, and modifications in the detailed character and sequential relation of the process steps and relationships as hereinbefore exemplified may be had without departing from the spirit of our invention, we wish to be understood as being limited solely by the scope of the appended claims, rather than by any particularities of the illustrative showing and foregoing description.

We claim as our invention:

1. The denture-characterizing process which consists of developing a conventional denture matrix interrupted by the bases of the teeth to be carried by the ultimate denture, forming in said matrix a pattern of the denture base labial portion thereby defined, trimming from said pattern the material about and outwardly contiguous to the tooth sockets corresponding with the lighter-colored alveolar zone tissue of a natural gum, applying said trimmed pattern to the development of a second matrix, drawing from said second matrix a reproduction of the trimmed pattern in thermo-setting pliable dough material containing vein-simulating fiber filaments, investing said reproduction in registered relation with said conventional matrix, applying unfibered thermo-setting pliable dough material to and as the alveolar zone of said reproduction prior to closing of the conventional matrix, pressureconsolidating the associated fibered and unfibered materials while in pliable condition through closing of the conventional matrix, and heat-curing the so-consolidated materials under maintained pressure and into consequent secure mounting engagement with the matrix-interrupting tooth bases.

2. The process according to claim 1, characterized by a packing of superposed laminae of thermo-setting pliable dough material in said second matrix to form said pattern reproduction and the patterned interposition of fiber filaments between contacting surfaces of said laminae as an incident of such packing.

3. The process according to claim 1, characterized by a selective tinting of the pliable dough material from which the pattern reproduction is formed, a distinctive tinting of the fiber filaments carried by the reproductionforming material, and a tinting of the unfibered alveolar zone pliable dough material differing from that of the pattern reproduction.

4. The process of making dentures which comprises the steps of developing a conventional denture matrix interrupted by the bases of the teeth to be carried by said denture, utilizing said matrix to form a pattern of the denture base labial portion, removing portions of said pattern contiguous to the tooth sockets and corresponding with the lighter colored alveolar zone tissue of a natural gum, utilizing said pattern to develop a second matrix, packing said second matrix with layers of uncured pliable thermo-setting material to provide a laminated reproduction of said pattern, certain of said layers having secured thereto vein-simulating fibers filaments arranged in a pre-determined pattern, investing said reproduction in registered relation with said first matrix, filling the alveolar zone of said reproduction with uncured pliable thermo-setting material free of fiber filaments, closing said first matrix under sufiicient pressure to mold said fiber containing and said fiber free material into a homogeneous mass embracing the bases of said teeth and complementary to said first matrix and applying snflicient heat to cure and set said materials thereby providing a completed denture including gums substantially simulating those of a person.

5. The process of making dentures which comprises the steps of developing a conventional denture matrix interrupted by the bases of the teeth to be carried by said denture, utilizing said matrix to form a pattern of the denture base labial portion, removing portions of said pattern contiguous to the tooth sockets and corresponding with the lighter colored alveolar zone tissue of a natural gum, utilizing said pattern to develop a second matrix, packing said second matrix with uncured pliable thermosetting material to provide a reproduction of said pattern, said material containing vein-simulating fiber filaments arranged in a pre-determined pattern, investing said reproduction in registered relation with said first matrix, filling the alveolar zone of said reproduction with uncured pliable thermo-setting material free of fiber filaments, closing said first matrix under sutficient pressure to mold said fiber containing and said fiber free material into a homogeneous mass embracing the bases of said teeth and complementary to said first matrix and applying sufficient heat to cure and set said materials thereby providing a completed denture including gums substantially simulating those of a person.

References Cited in the file of this patent UNITED STATES PATENTS 2,341,604 Dresch Feb. 15, 1944 2,497,873 Erpf Feb. 21, 1950 OTHER REFERENCES Glass Fibers as Acrylic Strengtheners, publication in Dental Digest, April 1945, page 190.

A new Natural Look for Acrylic Dentures, advertisement in Dental Digest, June 1948, page 278.

Resilient Resins: Technique For Their Use In Complete and Partial Dentures, Dental Digest, May 1944, pages 204-209; pages 208-209 particularly relied upon. 

1. THE DENTURE-CHARACTERIZING PROCESS WHICH CONSISTS OF DEVELOPING A CONVENTIONAL DENTURE MATRIX INTERRUPTED BY THE BASES OF THE TEETH TO BE CARRIED BY THE ULTIMATE DENTURE, FORMING IN SAID MATRIX A PATTERN OF THE DENTURE BASE LABIAL PORTION THEREBY DEFINED TRIMMING FROM SAID PATTERN THE MATERIAL ABOUT AND OUTWARDLY CONTIGUOUS TO THE TOOTH SOCKETS CORRESPONDING WITH THE LIGHTER-COLORED ALVEOLAR ZONE TISSUE OF A NATURAL GUM, APPLYING SAID TRIMMED PATTERN TO THE DEVELOPMENT OF A SECOND MATRIX, DRAWING FROM SAID SECOND MATRIX A REPRODUCTION OF THE TRIMMED PATTERN IN THERMO-SETTING PLIABLE DOUGH MATERIAL CONTAINING VEIN-SIMULATING FIBER FILAMENTS, INVESTING SAID REPRODUCTION IN REGISTERED RELATION WITH SAID CONVENTIONAL MATRIX, APPLYING UNFIBERED THERMO-SETTING PLIABLE DOUGH MATERIAL TO AND AS THE ALVEOLAR ZONE OF SAID REPRODUCTION PRIOR TO CLOSING OF THE CONVENTIONAL MATRIX, PRESSURECONSOLIDATING THE ASSOCIATED FIBERED AND UNFIBERED MATERIALS WHILE IN PLIABLE CONDITION THROUGH CLOSING OF THE CONVENTIONAL MATRIX, AND HEAT-CURING THE SO-CONSOLIDATED MATERIALS UNDER MAINTAINED PRESSURE AND INTO CONSEQUENT SECURE MOUNTING ENGAGEMENT WITH THE MATRIX-INTERRUPTING TOOTH BASES. 